The agency estimates there could be as many as 22.5 million people working by 2031, up from 18.5 million last year.
However, it projects that the rate of growth will slow to between 0.2 per cent and 0.7 per cent a year from 2021 to 2026. When the boomers were entering the job market in the 1970s, the labour force increased at an average rate of just over four per cent a year.
In 1981, there were roughly six people working for each retiree. By 2031, the ratio will be three to one, Statistics Canada forecasts. By that time, the entire baby-boom generation will have reached the age of 65.
The agency also projects that the participation rate in the labour force by 2031 could be as low as it was in the 1970s, with less than 63 per cent of Canadians over the age of 15 at work.
"The projected decline in the overall participation rate over the next two decades would be largely attributable to demographic phenomena, such as the aging of the baby boom cohorts, increasing life expectancy and a fertility rate below the replacement level of 2.1 children per woman," StatsCan said in a release.
Canada's workforce is not only aging, it is also becoming more ethnically diverse. StatsCan estimates that by 2031, roughly one in every three people in the labour force could be foreign born.
Even if there was no immigration for the next 30 years, the number of visible minorities in the workplace would be expected to increase.
Visible minority communities in Canada tend to be younger, so fewer members will be retiring over the next three decades, StatsCan said. Their children will also be entering the workforce.